Source Modes

The PXIe-4139 channels can generate voltage and current in Single Point or Sequence source mode.

Within Single Point and Sequence source mode, you can output the following:

  • DC voltage
  • DC current
  • Pulse voltage
  • Pulse current

The Source Mode With Channels function defines the source mode the PXIe-4139 channels are operating in.

Single Point Source Mode

In Single Point source mode, the source unit applies a single source configuration when it enters the Running state.

You can then update the source configuration dynamically (when a channel is in the Running state) by modifying those properties that support dynamic reconfiguration.

Sequence Source Mode

In Sequence source mode, the source unit steps through a predetermined set of source configurations. Each sequence comprises a series of outputs for an NI-DCPower channel.

Sequence source mode encompasses two types of sequences:

  • Simple sequence—Allows you to define a series of voltage outputs or current outputs and source delays for a single channel.
  • Advanced sequence—Allows you to define numerous properties per sequence step, in addition to basic voltage outputs or current outputs and source delays, for any number of channels.
    • Note You cannot program both simple sequences and advanced sequences within the same session.

    A channel steps through a sequence without any interaction between the host system and NI-DCPower. Because the host system is not involved in executing the changes between steps of the sequence, the changes between steps in a sequence are deterministic.

    Sequence Step Delta Time

    The PXIe-4139 supports configurable step duration for sequences through the Sequence Step Delta Time property.

    Note Sequence step delta time is supported with only DC voltage and DC current outputs; it is not supported with pulse voltage and pulse current outputs.

    Simple Sequences versus Advanced Sequences

    In Sequence Source Mode, you can use either simple sequencing or advanced sequencing. Each sequencing type has distinct capabilities and each is supported differently.

    Task Simple Sequencing Advanced Sequencing
    How to create Set the Source Mode to Sequence and use the Set Sequence function Set the Source Mode to Sequence; use the Create Advanced Sequence With Channels function, related advanced sequencing functions, and individual NI-DCPower properties
    What you can configure Voltage or current levels per step of the sequence, along with Source Delay for each step A wide variety of NI-DCPower properties per step of the sequence
    Channels the sequence applies to
    • LabVIEW NXG: single channel only
    • Other environments: any number of channels
    		 Any number of channels
    Controlling the initial state Manually configure the channel(s) before calling the Set Sequence function You can create a Commit step to configure channels to a known state before the sequence runs
    Importing and exporting sequences No capability Can be transferred between sessions with the Export Attribute Configuration and Import Attribute Configuration functions
    Note You cannot program both simple sequences and advanced sequences within the same session.

    Refer to the NI-DCPower examples in your application development environment to see how you can program with simple sequences and advanced sequences.

    Pulse Outputs

    The PXIe-4139 can output configurable current pulses and/or voltage pulses.

    You can use pulse outputs in either Single Point or Sequence source mode and can configure a wide variety of pulse characteristics to suit your application.

    The PXIe-4139 supports in-range pulsing and extended range pulsing.

  • In-range—Pulses fall within DC range limits.
  • Extended range—Pulses fall outside DC range limits for either current or power. Extended range pulsing is subject to additional limitations as described in the PXIe-4139 Specifications .